近年來無線網狀網路(Wireless Mesh Networks)備受矚目，無線網狀網路繼承原有的ad hoc networks的特性並提供階層式及多網卡的網路存取架構。在multi-hop networks下，傳輸功率的控制和網路路由的選擇是重要的議題，因為不同的傳輸功率產生不同的網路拓墣連結性和干擾。此外，在不同網路卡間的路由選擇也會產生不同程度的intra/inter-flow 干擾。這些特性對網路效能有密切的影響，過去相關的路由協定設計也大多未同時考量傳輸功率控制與多網路卡的特性。
在這篇論文中，我們提出了跨網路協定層的路由協定，稱作M2iRi2，同時考量傳輸功率的控制並將Intra/Inter-flow的干擾導入到路由路徑的選擇。節點上的網路卡在物理層(Physical layer) 計算目前對潛在可容忍的新增干擾，並將此訊息送到網路層(Network layer)和鄰居節點作交換。透過此資訊的交換，在路由發現時控制路由請求封包的傳輸功率，當路由建立後，封包根據路由表的記載，選擇所對應的路由路徑和傳輸功率。經由NS-2模擬結果顯示，我們所提出的跨網路協定層路由協定可同時兼顧網路的吞吐量和平均點對點的延遲。

In recent years, WMNs (Wireless Mesh Networks) technologies have received significant attentions. WMNs not only accede to the advantages of ad hoc networks but also provide hierarchical multi-interface architecture. Transmission power control and routing path selections are critical issues in the past researches of multi-hop networks. Variable transmission power levels lead to different network connectivity and interference. Further, routing path selections among different radio interfaces will also produce different intra/inter-flow interference. These features tightly affect the network performance. Most of the related works on routing protocol design do not consider transmission power control and multi-interface environment simultaneously.
In this thesis, we proposed a cross-layer routing protocol called M2iRi2 which coordinates transmission power control and intra/inter-flow interference considerations as routing metrics. Each radio interface calculates the potential tolerable added transmission interference in the physical layer. When the route discovery starts, the M2iRi2 will adopt the appropriate power level to evaluate each interface quality along paths. The simulation results demonstrate that our protocol can enhance both network throughput and end-to-end delay.

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